TITLE: GCN CIRCULAR NUMBER: 14063 SUBJECT: GRB 121211A: Swift/UVOT Detection DATE: 12/12/12 03:15:42 GMT FROM: Margaret Chester at PSU M. M. Chester (PSU) and V. Mangano (INAF-IASFPA) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 121211A 97 s after the BAT trigger (Mangano et al., GCN Circ. 14057). A source consistent with the enhanced Swift-XRT position (Osborne et al. GCN Circ. 14060) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 13:02:07.99 = 195.53328 (deg.) Dec (J2000) = +30:08:54.6 = 30.14849 (deg.) with an estimated uncertainty of 0.52 arc sec. (radius, 90% confidence). The following table provides preliminary detections and 3-sigma upper limits for the finding charts and summed exposures using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373). The lack of a detection in uvw2 is consistent with the redshift of 1.023 reported by Perley et al. (GCN Circ. 14059). Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 97 247 147 18.4 +/- 0.1 white 4103 5738 393 19.9 +/- 0.1 v 4514 6148 393 >19.9 b 3899 5533 393 20.4 +/- 0.2 u_FC 255 297 41 18.3 +/- 0.3 u 5128 5328 197 19.6 +/- 0.2 w1 10576 11476 886 20.6 +/- 0.2 m2 4718 10569 1082 20.6 +/- 0.2 w2 4309 5943 393 >21.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.01 in the direction of the burst (Schlegel et al. 1998).